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UniProtKB - P09871 (C1S_HUMAN)

Protein

Complement C1s subcomponent

Gene

C1S

Organism
Homo sapiens (Human)
Status
Reviewed-Annotation score:

Annotation score:5 out of 5

<p>The annotation score provides a heuristic measure of the annotation content of a UniProtKB entry or proteome. This score <strong>cannot</strong> be used as a measure of the accuracy of the annotation as we cannot define the ‘correct annotation’ for any given protein.<p><a href='/help/annotation_score' target='_top'>More...</a></p>-Experimental evidence at protein leveli <p>This indicates the type of evidence that supports the existence of the protein. Note that the ‘protein existence’ evidence does not give information on the accuracy or correctness of the sequence(s) displayed.<p><a href='/help/protein_existence' target='_top'>More...</a></p>

<p>This section provides any useful information about the protein, mostly biological knowledge.<p><a href='/help/function_section' target='_top'>More...</a></p>Functioni

C1s B chain is a serine protease that combines with C1q and C1r to form C1, the first component of the classical pathway of the complement system. C1r activates C1s so that it can, in turn, activate C2 and C4.

<p>This subsection of the <a href="http://www.uniprot.org/help/function_section">Function</a> section describes the catalytic activity of an enzyme, i.e. a chemical reaction that the enzyme catalyzes.<p><a href='/help/catalytic_activity' target='_top'>More...</a></p>Catalytic activityi

  • Cleavage of Arg-|-Ala bond in complement component C4 to form C4a and C4b, and Lys(or Arg)-|-Lys bond in complement component C2 to form C2a and C2b: the 'classical' pathway C3 convertase.1 Publication EC:3.4.21.42

<p>This subsection of the ‘Function’ section describes regulatory mechanisms for enzymes, transporters or microbial transcription factors, and reports the components which regulate (by activation or inhibition) the reaction.<p><a href='/help/activity_regulation' target='_top'>More...</a></p>Activity regulationi

Inhibited by SERPING1.1 Publication

<p>This subsection of the ‘Function’ section describes biophysical and chemical properties, such as maximal absorption, kinetic parameters, pH dependence, redox potentials and temperature dependence.<p><a href='/help/biophysicochemical_properties' target='_top'>More...</a></p>Kineticsi

Less efficient than MASP2 in C4 cleavage.
  1. KM=12.3 µM for complement component C2 (at 37 degrees Celsius)1 Publication
  2. KM=1.9 µM for complement component C4 (at 37 degrees Celsius)1 Publication

    Sites

    Feature keyPosition(s)DescriptionActionsGraphical viewLength
    <p>This subsection of the ‘Function’ section indicates at which position the protein binds a given metal ion. The nature of the metal is indicated in the ‘Description’ field.<p><a href='/help/metal' target='_top'>More...</a></p>Metal bindingi60Calcium1
    Metal bindingi68Calcium1
    Metal bindingi113Calcium1
    Metal bindingi131Calcium1
    Metal bindingi132Calcium; via carbonyl oxygen1
    Metal bindingi134Calcium1
    Metal bindingi149Calcium1
    Metal bindingi150Calcium; via carbonyl oxygen1
    Metal bindingi153Calcium; via carbonyl oxygen1
    <p>This subsection of the ‘Function’ section is used for enzymes and indicates the residues directly involved in catalysis.<p><a href='/help/act_site' target='_top'>More...</a></p>Active sitei475Charge relay system1
    Active sitei529Charge relay system1
    Active sitei632Charge relay system1

    <p>The <a href="http://www.geneontology.org/">Gene Ontology (GO)</a> project provides a set of hierarchical controlled vocabulary split into 3 categories:<p><a href='/help/gene_ontology' target='_top'>More...</a></p>GO - Molecular functioni

    • calcium ion binding Source: InterPro
    • identical protein binding Source: IntAct
    • serine-type endopeptidase activity Source: UniProtKB
    View the complete GO annotation on QuickGO ...

    GO - Biological processi

    View the complete GO annotation on QuickGO ...

    <p>UniProtKB Keywords constitute a <a href="http://www.uniprot.org/keywords">controlled vocabulary</a> with a hierarchical structure. Keywords summarise the content of a UniProtKB entry and facilitate the search for proteins of interest.<p><a href='/help/keywords' target='_top'>More...</a></p>Keywordsi

    Molecular functionHydrolase, Protease, Serine protease
    Biological processComplement pathway, Immunity, Innate immunity
    LigandCalcium, Metal-binding

    Enzyme and pathway databases

    BRENDA Comprehensive Enzyme Information System

    More...    BRENDAi    		3.4.21.42 2681

    Reactome - a knowledgebase of biological pathways and processes

    More...    Reactomei    		R-HSA-166663 Initial triggering of complement
    R-HSA-173623 Classical antibody-mediated complement activation
    R-HSA-977606 Regulation of Complement cascade

    SABIO-RK: Biochemical Reaction Kinetics Database

    More...    SABIO-RKi    		P09871

    Protein family/group databases

    MEROPS protease database

    More...    MEROPSi    		S01.193

    <p>This section provides information about the protein and gene name(s) and synonym(s) and about the organism that is the source of the protein sequence.<p><a href='/help/names_and_taxonomy_section' target='_top'>More...</a></p>Names & Taxonomyi

    <p>This subsection of the <a href="http://www.uniprot.org/help/names_and_taxonomy_section">Names and taxonomy</a> section provides an exhaustive list of all names of the protein, from commonly used to obsolete, to allow unambiguous identification of a protein.<p><a href='/help/protein_names' target='_top'>More...</a></p>Protein namesi
    Recommended name:
    Complement C1s subcomponent (EC:3.4.21.42)
    Alternative name(s):
    C1 esterase
    Complement component 1 subcomponent s
    Cleaved into the following 2 chains:
    Complement C1s subcomponent heavy chain
    Complement C1s subcomponent light chain
    <p>This subsection of the <a href="http://www.uniprot.org/help/names_and_taxonomy_section">Names and taxonomy</a> section indicates the name(s) of the gene(s) that code for the protein sequence(s) described in the entry. Four distinct tokens exist: ‘Name’, ‘Synonyms’, ‘Ordered locus names’ and ‘ORF names’.<p><a href='/help/gene_name' target='_top'>More...</a></p>Gene namesi
    Name:C1S
    <p>This subsection of the <a href="http://www.uniprot.org/help/names_and_taxonomy_section">Names and taxonomy</a> section provides information on the name(s) of the organism that is the source of the protein sequence.<p><a href='/help/organism-name' target='_top'>More...</a></p>OrganismiHomo sapiens (Human)
    <p>This subsection of the <a href="http://www.uniprot.org/help/names_and_taxonomy_section">Names and taxonomy</a> section shows the unique identifier assigned by the NCBI to the source organism of the protein. This is known as the ‘taxonomic identifier’ or ‘taxid’.<p><a href='/help/taxonomic_identifier' target='_top'>More...</a></p>Taxonomic identifieri9606 [NCBI]
    <p>This subsection of the <a href="http://www.uniprot.org/help/names_and_taxonomy_section">Names and taxonomy</a> section contains the taxonomic hierarchical classification lineage of the source organism. It lists the nodes as they appear top-down in the taxonomic tree, with the more general grouping listed first.<p><a href='/help/taxonomic_lineage' target='_top'>More...</a></p>Taxonomic lineageiEukaryota › Metazoa › Chordata › Craniata › Vertebrata › Euteleostomi › Mammalia › Eutheria › Euarchontoglires › Primates › Haplorrhini › Catarrhini › Hominidae › Homo
    <p>This subsection of the <a href="http://www.uniprot.org/help/names_and_taxonomy_section">Names and taxonomy</a> section is present for entries that are part of a <a href="http://www.uniprot.org/proteomes">proteome</a>, i.e. of a set of proteins thought to be expressed by organisms whose genomes have been completely sequenced.<p><a href='/help/proteomes_manual' target='_top'>More...</a></p>Proteomesi
    • UP000005640 <p>A UniProt <a href="http://www.uniprot.org/manual/proteomes_manual">proteome</a> can consist of several components. <br></br>The component name refers to the genomic component encoding a set of proteins.<p><a href='/help/proteome_component' target='_top'>More...</a></p> Componenti: Chromosome 12

    Organism-specific databases

    Eukaryotic Pathogen Database Resources

    More...    EuPathDBi    		HostDB:ENSG00000182326.14

    Human Gene Nomenclature Database

    More...    HGNCi    		HGNC:1247 C1S

    Online Mendelian Inheritance in Man (OMIM)

    More...    MIMi    		120580 gene

    neXtProt; the human protein knowledge platform

    More...    neXtProti    		NX_P09871

    <p>This section provides information on the location and the topology of the mature protein in the cell.<p><a href='/help/subcellular_location_section' target='_top'>More...</a></p>Subcellular locationi

    Extracellular region or secreted Cytosol Plasma membrane Cytoskeleton Lysosome Endosome Peroxisome ER Golgi apparatus Nucleus Mitochondrion Manual annotation Automatic computational assertionGraphics by Christian Stolte; Source: COMPARTMENTS

    <p>This section provides information on the disease(s) and phenotype(s) associated with a protein.<p><a href='/help/pathology_and_biotech_section' target='_top'>More...</a></p>Pathology & Biotechi

    <p>This subsection of the ‘Pathology and Biotech’ section provides information on the disease(s) associated with genetic variations in a given protein. The information is extracted from the scientific literature and diseases that are also described in the <a href="http://www.ncbi.nlm.nih.gov/sites/entrez?db=omim">OMIM</a> database are represented with a <a href="http://www.uniprot.org/diseases">controlled vocabulary</a> in the following way:<p><a href='/help/involvement_in_disease' target='_top'>More...</a></p>Involvement in diseasei

    Complement component C1s deficiency (C1SD)1 Publication
    The disease is caused by mutations affecting the gene represented in this entry.
    Disease descriptionA rare defect resulting in C1 deficiency and impaired activation of the complement classical pathway. C1 deficiency generally leads to severe immune complex disease with features of systemic lupus erythematosus and glomerulonephritis.
    See also OMIM:613783
    Ehlers-Danlos syndrome, periodontal type, 2 (EDSPD2)1 Publication
    The disease is caused by mutations affecting the gene represented in this entry.
    Disease descriptionA form of Ehlers-Danlos syndrome, a connective tissue disorder characterized by hyperextensible skin, atrophic cutaneous scars due to tissue fragility and joint hyperlaxity. EDSPD2 is characterized by the association of typical features of Ehlers-Danlos syndrome with gingival recession and severe early-onset periodontal disease, leading to premature loss of permanent teeth. EDSPD2 transmission pattern is consistent with autosomal dominant inheritance.
    See also OMIM:617174
    Feature keyPosition(s)DescriptionActionsGraphical viewLength
    <p>This subsection of the ‘Sequence’ section describes natural variant(s) of the protein sequence.<p><a href='/help/variant' target='_top'>More...</a></p>Natural variantiVAR_077120294C → R in EDSPD2. 1 PublicationCorresponds to variant dbSNP:rs886040975EnsemblClinVar.1
    Natural variantiVAR_077121316Missing in EDSPD2; unknown pathological significance. 1 Publication1

    Keywords - Diseasei

    Disease mutation, Ehlers-Danlos syndrome

    Organism-specific databases

    DisGeNET

    More...    DisGeNETi    		716

    MalaCards human disease database

    More...    MalaCardsi    		C1S
    MIMi613783 phenotype
    617174 phenotype

    Open Targets

    More...    OpenTargetsi    		ENSG00000182326

    Orphanet; a database dedicated to information on rare diseases and orphan drugs

    More...    Orphaneti    		75392 Ehlers-Danlos syndrome, periodontitis type
    169147 Immunodeficiency due to a classical component pathway complement deficiency

    The Pharmacogenetics and Pharmacogenomics Knowledge Base

    More...    PharmGKBi    		PA25636

    Chemistry databases

    ChEMBL database of bioactive drug-like small molecules

    More...    ChEMBLi    		CHEMBL3913

    Drug and drug target database

    More...    DrugBanki    		DB00054 Abciximab
    DB00051 Adalimumab
    DB00074 Basiliximab
    DB06404 C1 Esterase Inhibitor (Human)
    DB09228 C1 Esterase Inhibitor (Recombinant)
    DB00002 Cetuximab
    DB00005 Etanercept
    DB00056 Gemtuzumab ozogamicin
    DB00078 Ibritumomab tiuxetan
    DB00075 Muromonab
    DB00073 Rituximab
    DB00072 Trastuzumab

    IUPHAR/BPS Guide to PHARMACOLOGY

    More...    GuidetoPHARMACOLOGYi    		2335

    Polymorphism and mutation databases

    BioMuta curated single-nucleotide variation and disease association database

    More...    BioMutai    		C1S

    Domain mapping of disease mutations (DMDM)

    More...    DMDMi    		115205

    <p>This section describes post-translational modifications (PTMs) and/or processing events.<p><a href='/help/ptm_processing_section' target='_top'>More...</a></p>PTM / Processingi

    Molecule processing

    Feature keyPosition(s)DescriptionActionsGraphical viewLength
    <p>This subsection of the ‘PTM / Processing’ section denotes the presence of an N-terminal signal peptide.<p><a href='/help/signal' target='_top'>More...</a></p>Signal peptidei1 – 151 PublicationAdd BLAST15
    <p>This subsection of the ‘PTM / Processing’ section describes the extent of a polypeptide chain in the mature protein following processing.<p><a href='/help/chain' target='_top'>More...</a></p>ChainiPRO_000002758616 – 688Complement C1s subcomponentAdd BLAST673
    ChainiPRO_000002758716 – 437Complement C1s subcomponent heavy chainAdd BLAST422
    ChainiPRO_0000027588438 – 688Complement C1s subcomponent light chainAdd BLAST251

    Amino acid modifications

    Feature keyPosition(s)DescriptionActionsGraphical viewLength
    <p>This subsection of the PTM / Processing":/help/ptm_processing_section section describes the positions of cysteine residues participating in disulfide bonds.<p><a href='/help/disulfid' target='_top'>More...</a></p>Disulfide bondi65 ↔ 831 Publication
    Disulfide bondi135 ↔ 1471 Publication
    Disulfide bondi143 ↔ 1561 Publication
    <p>This subsection of the ‘PTM / Processing’ section specifies the position and type of each modified residue excluding <a href="http://www.uniprot.org/manual/lipid">lipids</a>, <a href="http://www.uniprot.org/manual/carbohyd">glycans</a> and <a href="http://www.uniprot.org/manual/crosslnk">protein cross-links</a>.<p><a href='/help/mod_res' target='_top'>More...</a></p>Modified residuei149(3R)-3-hydroxyasparagine1 Publication1
    Disulfide bondi158 ↔ 1711 Publication
    <p>This subsection of the <a href="http://www.uniprot.org/help/ptm_processing_section">PTM / Processing</a> section specifies the position and type of each covalently attached glycan group (mono-, di-, or polysaccharide).<p><a href='/help/carbohyd' target='_top'>More...</a></p>Glycosylationi174N-linked (GlcNAc...) asparagine2 Publications1
    Disulfide bondi175 ↔ 2021 Publication
    Disulfide bondi234 ↔ 2511 Publication
    Disulfide bondi294 ↔ 3411 Publication
    Disulfide bondi321 ↔ 3541 Publication
    Disulfide bondi359 ↔ 4031 Publication
    Disulfide bondi386 ↔ 4211 Publication
    Glycosylationi406N-linked (GlcNAc...) asparagine3 Publications1
    Disulfide bondi425 ↔ 549Interchain (between heavy and light chains)PROSITE-ProRule annotation1 Publication
    Disulfide bondi595 ↔ 6181 Publication
    Disulfide bondi628 ↔ 6591 Publication

    <p>This subsection of the <a href="http://www.uniprot.org/help/ptm_processing_section">PTM/processing</a> section describes post-translational modifications (PTMs). This subsection <strong>complements</strong> the information provided at the sequence level or describes modifications for which <strong>position-specific data is not yet available</strong>.<p><a href='/help/post-translational_modification' target='_top'>More...</a></p>Post-translational modificationi

    The iron and 2-oxoglutarate dependent 3-hydroxylation of aspartate and asparagine is (R) stereospecific within EGF domains.1 Publication

    Keywords - PTMi

    Disulfide bond, Glycoprotein, Hydroxylation

    Proteomic databases

    Encyclopedia of Proteome Dynamics

    More...    EPDi    		P09871

    MaxQB - The MaxQuant DataBase

    More...    MaxQBi    		P09871

    PaxDb, a database of protein abundance averages across all three domains of life

    More...    PaxDbi    		P09871

    PeptideAtlas

    More...    PeptideAtlasi    		P09871

    PRoteomics IDEntifications database

    More...    PRIDEi    		P09871

    ProteomicsDB human proteome resource

    More...    ProteomicsDBi    		52270

    2D gel databases

    Two-dimensional polyacrylamide gel electrophoresis database from the Geneva University Hospital

    More...    SWISS-2DPAGEi    		P09871

    PTM databases

    GlyConnect protein glycosylation platform

    More...    GlyConnecti    		1144

    iPTMnet integrated resource for PTMs in systems biology context

    More...    iPTMneti    		P09871

    Comprehensive resource for the study of protein post-translational modifications (PTMs) in human, mouse and rat.

    More...    PhosphoSitePlusi    		P09871

    Miscellaneous databases

    CutDB - Proteolytic event database

    More...    PMAP-CutDBi    		P09871

    <p>This section provides information on the expression of a gene at the mRNA or protein level in cells or in tissues of multicellular organisms.<p><a href='/help/expression_section' target='_top'>More...</a></p>Expressioni

    Gene expression databases

    Bgee dataBase for Gene Expression Evolution

    More...    Bgeei    		ENSG00000182326 Expressed in 230 organ(s), highest expression level in liver

    ExpressionAtlas, Differential and Baseline Expression

    More...    ExpressionAtlasi    		P09871 baseline and differential

    Genevisible search portal to normalized and curated expression data from Genevestigator

    More...    Genevisiblei    		P09871 HS

    Organism-specific databases

    Human Protein Atlas

    More...    HPAi    		CAB016722
    HPA018852

    <p>This section provides information on the quaternary structure of a protein and on interaction(s) with other proteins or protein complexes.<p><a href='/help/interaction_section' target='_top'>More...</a></p>Interactioni

    <p>This subsection of the <a href="http://www.uniprot.org/help/interaction_section">'Interaction'</a> section provides information about the protein quaternary structure and interaction(s) with other proteins or protein complexes (with the exception of physiological receptor-ligand interactions which are annotated in the <a href="http://www.uniprot.org/help/function_section">'Function'</a> section).<p><a href='/help/subunit_structure' target='_top'>More...</a></p>Subunit structurei

    C1 is a calcium-dependent trimolecular complex of C1q, C1r and C1s in the molar ration of 1:2:2. Activated C1s is an disulfide-linked heterodimer of a heavy chain and a light chain.1 Publication

    <p>This subsection of the '<a href="http://www.uniprot.org/help/interaction_section%27">Interaction</a> section provides information about binary protein-protein interactions. The data presented in this section are a quality-filtered subset of binary interactions automatically derived from the <a href="http://www.ebi.ac.uk/intact/">IntAct database</a>. It is updated on a monthly basis. Each binary interaction is displayed on a separate line.<p><a href='/help/binary_interactions' target='_top'>More...</a></p>Binary interactionsi

    GO - Molecular functioni

    View the complete GO annotation on QuickGO ...

    Protein-protein interaction databases

    The Biological General Repository for Interaction Datasets (BioGrid)

    More...    BioGridi    		107177, 7 interactors

    Protein interaction database and analysis system

    More...    IntActi    		P09871, 10 interactors

    Molecular INTeraction database

    More...    MINTi    		P09871

    STRING: functional protein association networks

    More...    STRINGi    		9606.ENSP00000328173

    Chemistry databases

    BindingDB database of measured binding affinities

    More...    BindingDBi    		P09871

    <p>This section provides information on the tertiary and secondary structure of a protein.<p><a href='/help/structure_section' target='_top'>More...</a></p>Structurei

    Secondary structure

    1688
    Legend: HelixTurnBeta strandPDB Structure known for this area
    Show more details

    3D structure databases

    Protein Model Portal of the PSI-Nature Structural Biology Knowledgebase

    More...    ProteinModelPortali    		P09871

    SWISS-MODEL Repository - a database of annotated 3D protein structure models

    More...    SMRi    		P09871

    Database of comparative protein structure models

    More...    ModBasei    		Search...

    MobiDB: a database of protein disorder and mobility annotations

    More...    MobiDBi    		Search...

    Miscellaneous databases

    Relative evolutionary importance of amino acids within a protein sequence

    More...    EvolutionaryTracei    		P09871

    <p>This section provides information on sequence similarities with other proteins and the domain(s) present in a protein.<p><a href='/help/family_and_domains_section' target='_top'>More...</a></p>Family & Domainsi

    Domains and Repeats

    Feature keyPosition(s)DescriptionActionsGraphical viewLength
    <p>This subsection of the <a href="http://www.uniprot.org/help/family_and_domains_section">Family and Domains</a> section describes the position and type of a domain, which is defined as a specific combination of secondary structures organized into a characteristic three-dimensional structure or fold.<p><a href='/help/domain' target='_top'>More...</a></p>Domaini16 – 130CUB 1PROSITE-ProRule annotationAdd BLAST115
    Domaini131 – 172EGF-like; calcium-bindingAdd BLAST42
    Domaini175 – 290CUB 2PROSITE-ProRule annotationAdd BLAST116
    Domaini292 – 356Sushi 1PROSITE-ProRule annotationAdd BLAST65
    Domaini357 – 423Sushi 2PROSITE-ProRule annotationAdd BLAST67
    Domaini438 – 680Peptidase S1PROSITE-ProRule annotationAdd BLAST243

    <p>This subsection of the ‘Family and domains’ section provides information about the sequence similarity with other proteins.<p><a href='/help/sequence_similarities' target='_top'>More...</a></p>Sequence similaritiesi

    Belongs to the peptidase S1 family.PROSITE-ProRule annotation

    Keywords - Domaini

    EGF-like domain, Repeat, Signal, Sushi

    Phylogenomic databases

    evolutionary genealogy of genes: Non-supervised Orthologous Groups

    More...    eggNOGi    		KOG3627 Eukaryota
    COG5640 LUCA

    Ensembl GeneTree

    More...    GeneTreei    		ENSGT00940000157473

    The HOVERGEN Database of Homologous Vertebrate Genes

    More...    HOVERGENi    		HBG000559

    InParanoid: Eukaryotic Ortholog Groups

    More...    InParanoidi    		P09871

    KEGG Orthology (KO)

    More...    KOi    		K01331

    Identification of Orthologs from Complete Genome Data

    More...    OMAi    		PENSRCD

    Database of Orthologous Groups

    More...    OrthoDBi    		EOG091G02DS

    Database for complete collections of gene phylogenies

    More...    PhylomeDBi    		P09871

    TreeFam database of animal gene trees

    More...    TreeFami    		TF330373

    Family and domain databases

    Conserved Domains Database

    More...    CDDi    		cd00033 CCP, 2 hits
    cd00041 CUB, 2 hits
    cd00190 Tryp_SPc, 1 hit

    Gene3D Structural and Functional Annotation of Protein Families

    More...    Gene3Di    		2.60.120.290, 2 hits

    Integrated resource of protein families, domains and functional sites

    More...    InterProi    		View protein in InterPro
    IPR035708 Complement_C1s_subcomponent
    IPR000859 CUB_dom
    IPR001881 EGF-like_Ca-bd_dom
    IPR000152 EGF-type_Asp/Asn_hydroxyl_site
    IPR018097 EGF_Ca-bd_CS
    IPR009003 Peptidase_S1_PA
    IPR001314 Peptidase_S1A
    IPR035914 Sperma_CUB_dom_sf
    IPR035976 Sushi/SCR/CCP_sf
    IPR000436 Sushi_SCR_CCP_dom
    IPR001254 Trypsin_dom
    IPR033116 TRYPSIN_SER

    The PANTHER Classification System

    More...    PANTHERi    		PTHR24255:SF18 PTHR24255:SF18, 1 hit

    Pfam protein domain database

    More...    Pfami    		View protein in Pfam
    PF00431 CUB, 2 hits
    PF00084 Sushi, 2 hits
    PF00089 Trypsin, 1 hit

    Protein Motif fingerprint database; a protein domain database

    More...    PRINTSi    		PR00722 CHYMOTRYPSIN

    Simple Modular Architecture Research Tool; a protein domain database

    More...    SMARTi    		View protein in SMART
    SM00032 CCP, 2 hits
    SM00042 CUB, 2 hits
    SM00179 EGF_CA, 1 hit
    SM00020 Tryp_SPc, 1 hit

    Superfamily database of structural and functional annotation

    More...    SUPFAMi    		SSF49854 SSF49854, 2 hits
    SSF50494 SSF50494, 1 hit
    SSF57535 SSF57535, 2 hits

    PROSITE; a protein domain and family database

    More...    PROSITEi    		View protein in PROSITE
    PS00010 ASX_HYDROXYL, 1 hit
    PS01180 CUB, 2 hits
    PS01187 EGF_CA, 1 hit
    PS50923 SUSHI, 2 hits
    PS50240 TRYPSIN_DOM, 1 hit
    PS00135 TRYPSIN_SER, 1 hit

    <p>This section displays by default the canonical protein sequence and upon request all isoforms described in the entry. It also includes information pertinent to the sequence(s), including <a href="http://www.uniprot.org/help/sequence_length">length</a> and <a href="http://www.uniprot.org/help/sequences">molecular weight</a>.<p><a href='/help/sequences_section' target='_top'>More...</a></p>Sequence (1+)i

    <p>This subsection of the <a href="http://www.uniprot.org/help/sequences_section">Sequence</a> section indicates if the <a href="http://www.uniprot.org/help/canonical_and_isoforms">canonical sequence</a> displayed by default in the entry is complete or not.<p><a href='/help/sequence_status' target='_top'>More...</a></p>Sequence statusi: Complete.

    <p>This subsection of the <a href="http://www.uniprot.org/help/sequences_section">Sequence</a> section indicates if the <a href="http://www.uniprot.org/help/canonical_and_isoforms">canonical sequence</a> displayed by default in the entry is in its mature form or if it represents the precursor.<p><a href='/help/sequence_processing' target='_top'>More...</a></p>Sequence processingi: The displayed sequence is further processed into a mature form.

    This entry has 1 described isoform and 7 potential isoforms that are computationally mapped.Show allAlign All

    P09871-1 [UniParc]FASTAAdd to basket
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            10         20         30         40         50
    MWCIVLFSLL AWVYAEPTMY GEILSPNYPQ AYPSEVEKSW DIEVPEGYGI 
            60         70         80         90        100
    HLYFTHLDIE LSENCAYDSV QIISGDTEEG RLCGQRSSNN PHSPIVEEFQ 
           110        120        130        140        150
    VPYNKLQVIF KSDFSNEERF TGFAAYYVAT DINECTDFVD VPCSHFCNNF 
           160        170        180        190        200
    IGGYFCSCPP EYFLHDDMKN CGVNCSGDVF TALIGEIASP NYPKPYPENS 
           210        220        230        240        250
    RCEYQIRLEK GFQVVVTLRR EDFDVEAADS AGNCLDSLVF VAGDRQFGPY 
           260        270        280        290        300
    CGHGFPGPLN IETKSNALDI IFQTDLTGQK KGWKLRYHGD PMPCPKEDTP 
           310        320        330        340        350
    NSVWEPAKAK YVFRDVVQIT CLDGFEVVEG RVGATSFYST CQSNGKWSNS 
           360        370        380        390        400
    KLKCQPVDCG IPESIENGKV EDPESTLFGS VIRYTCEEPY YYMENGGGGE 
           410        420        430        440        450
    YHCAGNGSWV NEVLGPELPK CVPVCGVPRE PFEEKQRIIG GSDADIKNFP 
           460        470        480        490        500
    WQVFFDNPWA GGALINEYWV LTAAHVVEGN REPTMYVGST SVQTSRLAKS 
           510        520        530        540        550
    KMLTPEHVFI HPGWKLLEVP EGRTNFDNDI ALVRLKDPVK MGPTVSPICL 
           560        570        580        590        600
    PGTSSDYNLM DGDLGLISGW GRTEKRDRAV RLKAARLPVA PLRKCKEVKV 
           610        620        630        640        650
    EKPTADAEAY VFTPNMICAG GEKGMDSCKG DSGGAFAVQD PNDKTKFYAA 
           660        670        680 
    GLVSWGPQCG TYGLYTRVKN YVDWIMKTMQ ENSTPRED
    Length:688
    Mass (Da):76,684
    Last modified:July 1, 1989 - v1
    <p>The checksum is a form of redundancy check that is calculated from the sequence. It is useful for tracking sequence updates.</p> <p>It should be noted that while, in theory, two different sequences could have the same checksum value, the likelihood that this would happen is extremely low.</p> <p>However UniProtKB may contain entries with identical sequences in case of multiple genes (paralogs).</p> <p>The checksum is computed as the sequence 64-bit Cyclic Redundancy Check value (CRC64) using the generator polynomial: x<sup>64</sup> + x<sup>4</sup> + x<sup>3</sup> + x + 1. The algorithm is described in the ISO 3309 standard. </p> <p class="publication">Press W.H., Flannery B.P., Teukolsky S.A. and Vetterling W.T.<br /> <strong>Cyclic redundancy and other checksums</strong><br /> <a href="http://www.nrbook.com/b/bookcpdf.php">Numerical recipes in C 2nd ed., pp896-902, Cambridge University Press (1993)</a>)</p> Checksum:i85522647A4C47205
    GO

    <p>In eukaryotic reference proteomes, unreviewed entries that are likely to belong to the same gene are computationally mapped, based on gene identifiers from Ensembl, EnsemblGenomes and model organism databases.<p><a href='/help/gene_centric_isoform_mapping' target='_top'>More...</a></p>Computationally mapped potential isoform sequencesi

    There are 7 potential isoforms mapped to this entry.BLASTAlignShow allAdd to basket
    EntryEntry nameProtein names
    		Gene namesLengthAnnotation
    A0A087X232A0A087X232_HUMAN
    Complement C1s subcomponent
    C1S
    		682Annotation score:

    Annotation score:2 out of 5

    <p>The annotation score provides a heuristic measure of the annotation content of a UniProtKB entry or proteome. This score <strong>cannot</strong> be used as a measure of the accuracy of the annotation as we cannot define the ‘correct annotation’ for any given protein.<p><a href='/help/annotation_score' target='_top'>More...</a></p>
    F8WCZ6F8WCZ6_HUMAN
    Complement C1s subcomponent
    C1S
    		521Annotation score:

    Annotation score:1 out of 5

    <p>The annotation score provides a heuristic measure of the annotation content of a UniProtKB entry or proteome. This score <strong>cannot</strong> be used as a measure of the accuracy of the annotation as we cannot define the ‘correct annotation’ for any given protein.<p><a href='/help/annotation_score' target='_top'>More...</a></p>
    B5MCV4B5MCV4_HUMAN
    Complement C1s subcomponent
    C1S
    		168Annotation score:

    Annotation score:1 out of 5

    <p>The annotation score provides a heuristic measure of the annotation content of a UniProtKB entry or proteome. This score <strong>cannot</strong> be used as a measure of the accuracy of the annotation as we cannot define the ‘correct annotation’ for any given protein.<p><a href='/help/annotation_score' target='_top'>More...</a></p>
    H0Y5D1H0Y5D1_HUMAN
    Complement C1s subcomponent
    C1S
    		355Annotation score:

    Annotation score:1 out of 5

    <p>The annotation score provides a heuristic measure of the annotation content of a UniProtKB entry or proteome. This score <strong>cannot</strong> be used as a measure of the accuracy of the annotation as we cannot define the ‘correct annotation’ for any given protein.<p><a href='/help/annotation_score' target='_top'>More...</a></p>
    C9JY52C9JY52_HUMAN
    Complement C1s subcomponent
    C1S
    		100Annotation score:

    Annotation score:1 out of 5

    <p>The annotation score provides a heuristic measure of the annotation content of a UniProtKB entry or proteome. This score <strong>cannot</strong> be used as a measure of the accuracy of the annotation as we cannot define the ‘correct annotation’ for any given protein.<p><a href='/help/annotation_score' target='_top'>More...</a></p>
    C9IZP8C9IZP8_HUMAN
    Complement C1s subcomponent
    C1S
    		103Annotation score:

    Annotation score:1 out of 5

    <p>The annotation score provides a heuristic measure of the annotation content of a UniProtKB entry or proteome. This score <strong>cannot</strong> be used as a measure of the accuracy of the annotation as we cannot define the ‘correct annotation’ for any given protein.<p><a href='/help/annotation_score' target='_top'>More...</a></p>
    F5H7T4F5H7T4_HUMAN
    Complement C1s subcomponent
    C1S
    		157Annotation score:

    Annotation score:1 out of 5

    <p>The annotation score provides a heuristic measure of the annotation content of a UniProtKB entry or proteome. This score <strong>cannot</strong> be used as a measure of the accuracy of the annotation as we cannot define the ‘correct annotation’ for any given protein.<p><a href='/help/annotation_score' target='_top'>More...</a></p>

    Experimental Info

    Feature keyPosition(s)DescriptionActionsGraphical viewLength
    <p>This subsection of the ‘Sequence’ section reports difference(s) between the canonical sequence (displayed by default in the entry) and the different sequence submissions merged in the entry. These various submissions may originate from different sequencing projects, different types of experiments, or different biological samples. Sequence conflicts are usually of unknown origin.<p><a href='/help/conflict' target='_top'>More...</a></p>Sequence conflicti294C → K AA sequence (PubMed:3007145).Curated1
    Sequence conflicti513G → GG (PubMed:2553984).Curated1
    Sequence conflicti573T → A AA sequence (PubMed:6362661).Curated1
    Sequence conflicti645 – 646TK → GR AA sequence (PubMed:6362661).Curated2

    Natural variant

    Feature keyPosition(s)DescriptionActionsGraphical viewLength
    Natural variantiVAR_033643119R → H. Corresponds to variant dbSNP:rs12146727Ensembl.1
    Natural variantiVAR_077120294C → R in EDSPD2. 1 PublicationCorresponds to variant dbSNP:rs886040975EnsemblClinVar.1
    Natural variantiVAR_077121316Missing in EDSPD2; unknown pathological significance. 1 Publication1
    Natural variantiVAR_033644327V → L. Corresponds to variant dbSNP:rs2239170Ensembl.1
    Natural variantiVAR_014565383R → H. Corresponds to variant dbSNP:rs20573Ensembl.1

    Sequence databases

    Select the link destinations:

    EMBL nucleotide sequence database

    More...    EMBLi

    GenBank nucleotide sequence database

    More...    GenBanki

    DNA Data Bank of Japan; a nucleotide sequence database

    More...    DDBJi
    Links Updated
    		X06596 mRNA Translation: CAA29817.1
    M18767 mRNA Translation: AAA51853.1
    J04080 mRNA Translation: AAA51852.1
    CH471116 Genomic DNA Translation: EAW88689.1
    CH471116 Genomic DNA Translation: EAW88690.1
    BC056903 mRNA Translation: AAH56903.1
    AB009076 Genomic DNA Translation: BAA86864.1

    The Consensus CDS (CCDS) project

    More...    CCDSi    		CCDS31735.1

    Protein sequence database of the Protein Information Resource

    More...    PIRi    		A40496 C1HUS

    NCBI Reference Sequences

    More...    RefSeqi    		NP_001333779.1, NM_001346850.1
    NP_001725.1, NM_001734.4
    NP_958850.1, NM_201442.3
    XP_005253817.1, XM_005253760.1

    UniGene gene-oriented nucleotide sequence clusters

    More...    UniGenei    		Hs.458355

    Genome annotation databases

    Ensembl eukaryotic genome annotation project

    More...    Ensembli    		ENST00000328916; ENSP00000328173; ENSG00000182326
    ENST00000360817; ENSP00000354057; ENSG00000182326
    ENST00000406697; ENSP00000385035; ENSG00000182326

    Database of genes from NCBI RefSeq genomes

    More...    GeneIDi    		716

    KEGG: Kyoto Encyclopedia of Genes and Genomes

    More...    KEGGi    		hsa:716

    UCSC genome browser

    More...    UCSCi    		uc001qsj.4 human

    Keywords - Coding sequence diversityi

    Polymorphism

    <p>This section provides links to proteins that are similar to the protein sequence(s) described in this entry at different levels of sequence identity thresholds (100%, 90% and 50%) based on their membership in UniProt Reference Clusters (<a href="http://www.uniprot.org/help/uniref">UniRef</a>).<p><a href='/help/similar_proteins_section' target='_top'>More...</a></p>Similar proteinsi

    <p>This section is used to point to information related to entries and found in data collections other than UniProtKB.<p><a href='/help/cross_references_section' target='_top'>More...</a></p>Cross-referencesi

    <p>This subsection of the <a href="http://www.uniprot.org/manual/cross_references_section">Cross-references</a> section provides links to various web resources that are relevant for a specific protein.<p><a href='/help/web_resource' target='_top'>More...</a></p>Web resourcesi

    C1Sbase

    C1S mutation db

    Sequence databases

    Select the link destinations:
    EMBLi
    GenBanki
    DDBJi
    Links Updated
    		X06596 mRNA Translation: CAA29817.1
    M18767 mRNA Translation: AAA51853.1
    J04080 mRNA Translation: AAA51852.1
    CH471116 Genomic DNA Translation: EAW88689.1
    CH471116 Genomic DNA Translation: EAW88690.1
    BC056903 mRNA Translation: AAH56903.1
    AB009076 Genomic DNA Translation: BAA86864.1
    CCDSiCCDS31735.1
    PIRiA40496 C1HUS
    RefSeqiNP_001333779.1, NM_001346850.1
    NP_001725.1, NM_001734.4
    NP_958850.1, NM_201442.3
    XP_005253817.1, XM_005253760.1
    UniGeneiHs.458355

    3D structure databases

    Select the link destinations:

    Protein Data Bank Europe

    More...    PDBei

    Protein Data Bank RCSB

    More...    RCSB PDBi

    Protein Data Bank Japan

    More...    PDBji
    Links Updated
    		PDB entryMethodResolution (Å)ChainPositionsPDBsum
    1ELVX-ray1.70A356-688[»]
    1NZIX-ray1.50A/B16-174[»]
    4J1YX-ray2.66A/B292-688[»]
    4LMFX-ray2.92A/B/C/D17-292[»]
    4LORX-ray2.50A17-292[»]
    4LOSX-ray2.00A172-358[»]
    4LOTX-ray2.92A175-423[»]
    6F1CX-ray4.20B/D16-292[»]
    6F1HX-ray4.50B/D17-292[»]
    ProteinModelPortaliP09871
    SMRiP09871
    ModBaseiSearch...
    MobiDBiSearch...

    Protein-protein interaction databases

    BioGridi107177, 7 interactors
    IntActiP09871, 10 interactors
    MINTiP09871
    STRINGi9606.ENSP00000328173

    Chemistry databases

    BindingDBiP09871
    ChEMBLiCHEMBL3913
    DrugBankiDB00054 Abciximab
    DB00051 Adalimumab
    DB00074 Basiliximab
    DB06404 C1 Esterase Inhibitor (Human)
    DB09228 C1 Esterase Inhibitor (Recombinant)
    DB00002 Cetuximab
    DB00005 Etanercept
    DB00056 Gemtuzumab ozogamicin
    DB00078 Ibritumomab tiuxetan
    DB00075 Muromonab
    DB00073 Rituximab
    DB00072 Trastuzumab
    GuidetoPHARMACOLOGYi2335

    Protein family/group databases

    MEROPSiS01.193

    PTM databases

    GlyConnecti1144
    iPTMnetiP09871
    PhosphoSitePlusiP09871

    Polymorphism and mutation databases

    BioMutaiC1S
    DMDMi115205

    2D gel databases

    SWISS-2DPAGEiP09871

    Proteomic databases

    EPDiP09871
    MaxQBiP09871
    PaxDbiP09871
    PeptideAtlasiP09871
    PRIDEiP09871
    ProteomicsDBi52270

    Protocols and materials databases

    Structural Biology KnowledgebaseSearch...

    Genome annotation databases

    EnsembliENST00000328916; ENSP00000328173; ENSG00000182326
    ENST00000360817; ENSP00000354057; ENSG00000182326
    ENST00000406697; ENSP00000385035; ENSG00000182326
    GeneIDi716
    KEGGihsa:716
    UCSCiuc001qsj.4 human

    Organism-specific databases

    Comparative Toxicogenomics Database

    More...    CTDi    		716
    DisGeNETi716
    EuPathDBiHostDB:ENSG00000182326.14

    GeneCards: human genes, protein and diseases

    More...    GeneCardsi    		C1S
    HGNCiHGNC:1247 C1S
    HPAiCAB016722
    HPA018852
    MalaCardsiC1S
    MIMi120580 gene
    613783 phenotype
    617174 phenotype
    neXtProtiNX_P09871
    OpenTargetsiENSG00000182326
    Orphaneti75392 Ehlers-Danlos syndrome, periodontitis type
    169147 Immunodeficiency due to a classical component pathway complement deficiency
    PharmGKBiPA25636

    GenAtlas: human gene database

    More...    GenAtlasi    		Search...

    Phylogenomic databases

    eggNOGiKOG3627 Eukaryota
    COG5640 LUCA
    GeneTreeiENSGT00940000157473
    HOVERGENiHBG000559
    InParanoidiP09871
    KOiK01331
    OMAiPENSRCD
    OrthoDBiEOG091G02DS
    PhylomeDBiP09871
    TreeFamiTF330373

    Enzyme and pathway databases

    BRENDAi3.4.21.42 2681
    ReactomeiR-HSA-166663 Initial triggering of complement
    R-HSA-173623 Classical antibody-mediated complement activation
    R-HSA-977606 Regulation of Complement cascade
    SABIO-RKiP09871

    Miscellaneous databases

    ChiTaRS: a database of human, mouse and fruit fly chimeric transcripts and RNA-sequencing data

    More...    ChiTaRSi    		C1S human
    EvolutionaryTraceiP09871

    The Gene Wiki collection of pages on human genes and proteins

    More...    GeneWikii    		C1S

    Database of phenotypes from RNA interference screens in Drosophila and Homo sapiens

    More...    GenomeRNAii    		716
    PMAP-CutDBiP09871

    Protein Ontology

    More...    PROi    		PR:P09871

    The Stanford Online Universal Resource for Clones and ESTs

    More...    SOURCEi    		Search...

    Gene expression databases

    BgeeiENSG00000182326 Expressed in 230 organ(s), highest expression level in liver
    ExpressionAtlasiP09871 baseline and differential
    GenevisibleiP09871 HS

    Family and domain databases

    CDDicd00033 CCP, 2 hits
    cd00041 CUB, 2 hits
    cd00190 Tryp_SPc, 1 hit
    Gene3Di2.60.120.290, 2 hits
    InterProiView protein in InterPro
    IPR035708 Complement_C1s_subcomponent
    IPR000859 CUB_dom
    IPR001881 EGF-like_Ca-bd_dom
    IPR000152 EGF-type_Asp/Asn_hydroxyl_site
    IPR018097 EGF_Ca-bd_CS
    IPR009003 Peptidase_S1_PA
    IPR001314 Peptidase_S1A
    IPR035914 Sperma_CUB_dom_sf
    IPR035976 Sushi/SCR/CCP_sf
    IPR000436 Sushi_SCR_CCP_dom
    IPR001254 Trypsin_dom
    IPR033116 TRYPSIN_SER
    PANTHERiPTHR24255:SF18 PTHR24255:SF18, 1 hit
    PfamiView protein in Pfam
    PF00431 CUB, 2 hits
    PF00084 Sushi, 2 hits
    PF00089 Trypsin, 1 hit
    PRINTSiPR00722 CHYMOTRYPSIN
    SMARTiView protein in SMART
    SM00032 CCP, 2 hits
    SM00042 CUB, 2 hits
    SM00179 EGF_CA, 1 hit
    SM00020 Tryp_SPc, 1 hit
    SUPFAMiSSF49854 SSF49854, 2 hits
    SSF50494 SSF50494, 1 hit
    SSF57535 SSF57535, 2 hits
    PROSITEiView protein in PROSITE
    PS00010 ASX_HYDROXYL, 1 hit
    PS01180 CUB, 2 hits
    PS01187 EGF_CA, 1 hit
    PS50923 SUSHI, 2 hits
    PS50240 TRYPSIN_DOM, 1 hit
    PS00135 TRYPSIN_SER, 1 hit

    ProtoNet; Automatic hierarchical classification of proteins

    More...    ProtoNeti    		Search...

    <p>This section provides general information on the entry.<p><a href='/help/entry_information_section' target='_top'>More...</a></p>Entry informationi

    <p>This subsection of the ‘Entry information’ section provides a mnemonic identifier for a UniProtKB entry, but it is not a stable identifier. Each reviewed entry is assigned a unique entry name upon integration into UniProtKB/Swiss-Prot.<p><a href='/help/entry_name' target='_top'>More...</a></p>Entry nameiC1S_HUMAN
    <p>This subsection of the ‘Entry information’ section provides one or more accession number(s). These are stable identifiers and should be used to cite UniProtKB entries. Upon integration into UniProtKB, each entry is assigned a unique accession number, which is called ‘Primary (citable) accession number’.<p><a href='/help/accession_numbers' target='_top'>More...</a></p>AccessioniPrimary (citable) accession number: P09871
    Secondary accession number(s): D3DUT4
    , Q9UCU7, Q9UCU8, Q9UCU9, Q9UCV0, Q9UCV1, Q9UCV2, Q9UCV3, Q9UCV4, Q9UCV5, Q9UM14
    <p>This subsection of the ‘Entry information’ section shows the date of integration of the entry into UniProtKB, the date of the last sequence update and the date of the last annotation modification (‘Last modified’). The version number for both the entry and the <a href="http://www.uniprot.org/help/canonical_and_isoforms">canonical sequence</a> are also displayed.<p><a href='/help/entry_history' target='_top'>More...</a></p>Entry historyiIntegrated into UniProtKB/Swiss-Prot: July 1, 1989
    Last sequence update: July 1, 1989
    Last modified: December 5, 2018
    This is version 228 of the entry and version 1 of the sequence. See complete history.
    <p>This subsection of the ‘Entry information’ section indicates whether the entry has been manually annotated and reviewed by UniProtKB curators or not, in other words, if the entry belongs to the Swiss-Prot section of UniProtKB (<strong>reviewed</strong>) or to the computer-annotated TrEMBL section (<strong>unreviewed</strong>).<p><a href='/help/entry_status' target='_top'>More...</a></p>Entry statusiReviewed (UniProtKB/Swiss-Prot)
    Annotation programChordata Protein Annotation Program
    DisclaimerAny medical or genetic information present in this entry is provided for research, educational and informational purposes only. It is not in any way intended to be used as a substitute for professional medical advice, diagnosis, treatment or care.

    <p>This section contains any relevant information that doesn’t fit in any other defined sections<p><a href='/help/miscellaneous_section' target='_top'>More...</a></p>Miscellaneousi

    Keywords - Technical termi

    3D-structure, Complete proteome, Direct protein sequencing, Reference proteome

    Documents

    1. PDB cross-references
      Index of Protein Data Bank (PDB) cross-references
    2. SIMILARITY comments
      Index of protein domains and families
    3. Human chromosome 12
      Human chromosome 12: entries, gene names and cross-references to MIM
    4. Peptidase families
      Classification of peptidase families and list of entries
    5. Human polymorphisms and disease mutations
      Index of human polymorphisms and disease mutations
    6. Human entries with polymorphisms or disease mutations
      List of human entries with polymorphisms or disease mutations
    7. MIM cross-references
      Online Mendelian Inheritance in Man (MIM) cross-references in UniProtKB/Swiss-Prot
    UniProt is an ELIXIR core data resource
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